Choose the person whose item you want to duplicate and the person you want to have the item when you get to the point in the game where you pick the Knights you are taking with you from the Round Table. The person that has the item must be killed and this will allow you to equip the item that they had on another Knight. Complete the mission and then let the game auto-save. At the beginning of the next mission, chose the same people. The guy that died still has the item and the Knight that you gave the item too has it as well. Repeat these steps to continually duplicate items.
Go on a missions and get the items that you want to keep. Fail the mission and reenter the mission. This time all the items you received will still be in your possession and the chests will contain money, unless you sell the item which would result in the item being in the chest.
To get some extra experience, go to the first town in the second mission and kill the chickens. Killing the pigs won't do anything.
Completing the Four Ancient Lords Tests at The Threshold Of Camelot
Note: Gwenevere cannot die or the mission will fail.
Test 1: Keep Gwenevere outside the area where you fight and order her to stay there and guard. Take Percival and Arthur with you into the area and kill the first Lord. This will award you with the first prize.
Test 2: Have Gwenevere and Percival attack ranged enemies. Take Arthur and defeat the arrow slinging Lord to receive the second prize.
Test 3: This is definitely the hardest test. For starters, the fake Gwenevere is the one right next to you when they start attacking each other. After a few hits he will turn to his true form, the Third Lord, and challenge you to a duel. To make it a lot easier, do the same as in the first test and take Gwenevere away from this magically-inclined Lord. The north seems the best direction, as it has stairwells you can put Gwenevere in to keep her out of range of the Lord's attacks. After that, Arthur and Percival should have an easier time attacking, and not worry about Gwenevere's dying. The silhouettes of the Lord will die after a few hits, giving you a better shot at hitting the real one. However, once all but the real one are gone he will bring them back. Keep hacking at him until he is defeated. If for any reason Arthur or Percival are in danger of dying, run them up to where Gwenevere is hiding and wait to heal them. Then, return to finish off the third Lord and claim your last prize. During the Test 3, an easy way to distinguish the real Lord is simply setting Percival to attack the Strongest. He will automatically go after the real Lord, and not the silhouettes.
Test 4: Don't pick up the Lord's gold and you shouldn't have any problems beating him. If you want a challenge, then pick up his gold and make him mad.